In recent years, Organic Light-Emitting Diode (OLED) displays have become very popular emerging flat display devices at home and abroad. Because the OLED display has the advantages of self-luminous, wide viewing angle, short reaction time, high luminous efficiency, wide color gamut, low operating voltage, thin thickness, can produce large size and flexible display and simple manufacturing process. And the OLED display has the potential of low cost.
In recent years, flexible and foldable OLED displays are the new focal points in the display industry. However, the contrast of flexible OLED displays may vary greatly depending on the external environment (mainly the intensity of the external ambient light). For example, in a bright environment, the external ambient light may be emitted in various layers, such as the organic electroluminescent layer and the thin film transistor layer of the flexible OLED display, another part of the external ambient light through the flexible OLED display, the light through the external environment of the flexible OLED display and the organic electroluminescent layer of light mixed to reduce the contrast of the screen, seriously affecting the product's effect.